Packs for Survival Blog

The first question you may ask yourself after reading a title like this is, “what kind of data is there to back up this kind of statement?” The answer may shock you, and get you to think about your own earthquake preparedness plans.

The West Coast according to geologists is overdue for a major earthquake. It is very difficult to predict when and where the next earthquake will strike, however, one of the best tools we have to assist in earthquake prediction is the historical data collected over hundreds of years. Technology brings us better and better tools each year, and scientists are able to gain a better understanding of earthquakes from the study of each occurrence.

Digging into earthquake data for the past ten years, and looking at quakes of at least a magnitude 6.5 or greater there are interesting patterns that start to emerge. Because the Pacific Rim is affected by the movement of the Pacific Plate, and in small part by the Nazca, and Philippine Plates, any shift will have effects on the whole system. Analysis of earthquake data for the past ten years shows that tectonic plate pressure and release in the subduction zones appears to move in a counterclockwise direction. For example if an earthquake occurs in Japan, this then changes the stress on the Pacific Plate in the South Pacific near the Tonga Region. The stress at this point may or may not be relieved in the form of an earthquake, but the stress is either continued, or transferred further counterclockwise to the South America region. Once again the stress may or may not be relieved in the form of an earthquake, but the stress continues to travel counterclockwise to North America. In many cases from our study the stress relief occurred in the form of earthquakes approximately equivalent in magnitude to the starting earthquake selected. North America, however, has not had an earthquake with similar magnitude strength since June 15th 2005, when a 7.2 magnitude quake struck offshore in northern California.

In the past 10,000 years there has been written and verbal history of earthquakes on the west coast of the United States. In all there have been no less than twenty 9.0 magnitude earthquakes affecting the Cascadia Subduction Zone just off the coast of Washington, Oregon, and California. In addition there were another 21 earthquakes that occurred just along the southern portion of this same subduction zone. That equates to 41 massive earthquakes that have occurred in this region in the past 10,000 years. Doing the math, that is one 9.0 earthquake about every 243 years on average. The last earthquake of that magnitude occurred on January 26th 1700. That quake lasted for 6-7 minutes building in strength and intensity. Once everything finally stopped shaking and people might have thought the worst was over, and then came the tsunami. There was a wall of water 30-50 feet high that came rushing across the coast, leaving a huge path of destruction.

In the Past eight years we have seen massively destructive earthquakes around the Pacific Rim:
-Magnitude 9.1 OFF THE WEST COAST OF NORTHERN SUMATRA December 26, 2004,
-Magnitude 8.0 TONGA REGION May 03, 2006,
-Magnitude 8.0 NEAR THE COAST OF CENTRAL PERU August 15, 2007,
-Magnitude 8.8 OFFSHORE BIO-BIO, CHILE February 27, 2010,
-Magnitude 9.0 NEAR THE EAST COAST OF HONSHU, JAPAN March 11, 2011
These monster earthquakes have occurred in every region around the Pacific Rim, with one exception, North America. One can only imagine the amount of stress building on the North American section of the Pacific Plate. Recounting that the last major earthquake along the Cascadia Subduction zone was 312 years ago, it becomes obvious that one is overdue by 69 years.

In looking at the data presented one has to think, what will my family do when this massive earthquake comes. Have you reviewed your emergency plan with your family lately? Do you have a meeting place following a disaster of this magnitude? Have you prepared or purchase enough supplies for you and your family for at least 72 hours minimum? If the answer to any of these questions was no, then what are you waiting for. Earthquakes are inevitable, Survival is optional. Get prepared today!